A novel rice fragile culm 24 mutant encodes a UDP-glucose epimerase that affects cell wall properties and photosynthesis

Abstract UDP-glucose epimerases (UGEs) are essential enzymes for catalysing the conversion of UDP-glucose (UDP-Glc) into UDP-galactose (UDP-Gal). Although UDP-Gal has been well studied as the substrate for the biosynthesis of carbohydrates, glycolipids, and glycoproteins, much remains unknown about the biological function of UGEs in plants. In this study, we selected a novel rice fragile culm 24 (Osfc24) mutant and identified it as a nonsense mutation of the FC24/OsUGE2 gene. The Osfc24 mutant shows a brittleness phenotype with significantly altered cell wall composition and disrupted orientation of the cellulose microfibrils. We found significantly reduced accumulation of arabinogalactan proteins in the cell walls of the mutant, which may consequently affect plant growth and cell wall deposition, and be responsible for the altered cellulose microfibril orientation. The mutant exhibits dwarfism and paler leaves with significantly decreased contents of galactolipids and chlorophyll, resulting in defects in plant photosynthesis. Based on our results, we propose a model for how OsUGE2 participates in two distinct metabolic pathways to co-modulate cellulose biosynthesis and cell wall assembly by dynamically providing UDP-Gal and UDP-Glc substrates.

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Staphylococcus aureus Mutants with Increased Lysostaphin Resistance

Journal of Bacteriology ◽

10.1128/jb.00457-06 ◽

2006 ◽

Vol 188 (17) ◽

pp. 6286-6297 ◽

Cited By ~ 70

Author(s):

Angelika Gründling ◽

Dominique M. Missiakas ◽

Olaf Schneewind

Keyword(s):

Staphylococcus Aureus ◽

Cell Wall ◽

Cell Wall Assembly ◽

Bacteriolytic Enzyme ◽

Transposon Insertion ◽

Transposon Mutants ◽

Altered Cell ◽

Cross Bridges ◽

Polytopic Membrane Protein ◽

Wall Assembly

ABSTRACT Staphylococcus simulans secretes lysostaphin, a bacteriolytic enzyme that specifically binds to the cell wall envelope of Staphylococcus aureus and cleaves the pentaglycine cross bridges of peptidoglycan, thereby killing staphylococci. The study of S. aureus mutants with resistance to lysostaphin-mediated killing has revealed biosynthetic pathways for cell wall assembly. To identify additional genes involved in cell wall envelope biosynthesis, we have screened a collection of S. aureus strain Newman transposon mutants for lysostaphin resistance. Bursa aurealis insertion in SAV2335, encoding a polytopic membrane protein with predicted protease domain, caused a high degree of lysostaphin resistance, similar to the case for a previously described femAB promoter mutant. In contrast to the case for this femAB mutant, transposon insertion in SAV2335, herein named lyrA (lysostaphin resistance A), did not cause gross alterations of cell wall cross bridges such as truncations of pentaglycine to tri- or monoglycine. Also, inactivation of LyrA in a methicillin-resistant S. aureus strain did not precipitate a decrease in β-lactam resistance as observed for fem (factor essential for methicillin resistance) mutants. Lysostaphin bound to the cell wall envelopes of lyrA mutants in a manner similar to that for wild-type staphylococci. Lysostaphin resistance of lyrA mutants is attributable to altered cell wall envelope properties and may in part be due to increased abundance of altered cross bridges. Other lyr mutants with intermediate lysostaphin resistance carried bursa aurealis insertions in genes specifying GTP pyrophosphokinase or enzymes of the purine biosynthetic pathway.

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Ultrastructural development of the softwood cell wall during pyrolysis

Holzforschung ◽

10.1515/hf.2009.031 ◽

2009 ◽

Vol 63 (2) ◽

Cited By ~ 16

Author(s):

Cordt Zollfrank ◽

Jörg Fromm

Keyword(s):

Cell Wall ◽

Elemental Composition ◽

Cellulose Microfibril ◽

Middle Lamella ◽

Cellulose Microfibrils ◽

Local Orientation ◽

Transmission Electron ◽

Cellulose Microfibril Orientation ◽

Novel Method ◽

Early Degradation

Abstract The pyrolytic conversion of pine wood at mild temperatures between 200°C and 300°C was investigated by transmission electron microscopy (TEM). Based on TEM imaging and image analysis, a novel method was developed for determining the local orientation of the cellulose microfibrils in the secondary wall S2 which gives a measure for the progression of pyrolytic conversion of the cell wall. Elemental composition of pyrolysed specimens was determined up to 600°C. TEM imaging together with the evaluation of the elemental composition shows that first the polyoses are degraded, while the cellulose microfibril orientation is still visible up to 225°C. The cellulose microfibrils could not be observed at temperatures higher than 250°C, while lignin containing compound middle lamella (CML) was still visible. After a gradual decrease of the CML up to 275°C, the cell wall became entirely isotropic beginning at 300°C. Based on the presented results, we propose an early degradation of the supramolecular structure of the cell wall.

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The discovery and biosynthesis of nucleoside antibiotics Inhibiting cell wall assembly

Planta Medica ◽

10.1055/s-0032-1320238 ◽

2012 ◽

Vol 78 (11) ◽

Author(s):

SG Van Lanen

Keyword(s):

Cell Wall ◽

Nucleoside Antibiotics ◽

Cell Wall Assembly ◽

Wall Assembly

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Faculty Opinions recommendation of A widespread family of bacterial cell wall assembly proteins.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.13363962.14734062 ◽

2011 ◽

Author(s):

Terry Roemer

Keyword(s):

Cell Wall ◽

Bacterial Cell ◽

Bacterial Cell Wall ◽

Cell Wall Assembly ◽

Wall Assembly ◽

Assembly Proteins

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The role of the exocytic pathway in cell wall assembly in yeast

Yeast ◽

10.1002/yea.3659 ◽

2021 ◽

Author(s):

Qingguo Guo ◽

Na Meng ◽

Guanzhi Fan ◽

Dong Sun ◽

Yuan Meng ◽

...

Keyword(s):

Cell Wall ◽

Cell Wall Assembly ◽

Wall Assembly ◽

Exocytic Pathway

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Hitting the Wall—Sensing and Signaling Pathways Involved in Plant Cell Wall Remodeling in Response to Abiotic Stress

Plants ◽

10.3390/plants7040089 ◽

2018 ◽

Vol 7 (4) ◽

pp. 89 ◽

Cited By ~ 38

Author(s):

Lazar Novaković ◽

Tingting Guo ◽

Antony Bacic ◽

Arun Sampathkumar ◽

Kim Johnson

Keyword(s):

Cell Wall ◽

Abiotic Stress ◽

Plant Hormones ◽

Plant Cell Wall ◽

Key Factors ◽

Cell Wall Remodeling ◽

Dynamic Cell ◽

Adverse Environmental Conditions ◽

Cell Wall Deposition ◽

Cell Wall Properties

Plant cells are surrounded by highly dynamic cell walls that play important roles regulating aspects of plant development. Recent advances in visualization and measurement of cell wall properties have enabled accumulation of new data about wall architecture and biomechanics. This has resulted in greater understanding of the dynamics of cell wall deposition and remodeling. The cell wall is the first line of defense against different adverse abiotic and biotic environmental influences. Different abiotic stress conditions such as salinity, drought, and frost trigger production of Reactive Oxygen Species (ROS) which act as important signaling molecules in stress activated cellular responses. Detection of ROS by still-elusive receptors triggers numerous signaling events that result in production of different protective compounds or even cell death, but most notably in stress-induced cell wall remodeling. This is mediated by different plant hormones, of which the most studied are jasmonic acid and brassinosteroids. In this review we highlight key factors involved in sensing, signal transduction, and response(s) to abiotic stress and how these mechanisms are related to cell wall-associated stress acclimatization. ROS, plant hormones, cell wall remodeling enzymes and different wall mechanosensors act coordinately during abiotic stress, resulting in abiotic stress wall acclimatization, enabling plants to survive adverse environmental conditions.

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Properties of Arabinogalactan Proteins (AGPs) in Apple (Malus × Domestica) Fruit at Different Stages of Ripening

Biology ◽

10.3390/biology9080225 ◽

2020 ◽

Vol 9 (8) ◽

pp. 225

Author(s):

Agata Leszczuk ◽

Justyna Cybulska ◽

Tomasz Skrzypek ◽

Artur Zdunek

Keyword(s):

Cell Wall ◽

Malus Domestica ◽

Arabinogalactan Proteins ◽

Ex Situ ◽

Morphological Properties ◽

Mature Stage ◽

Fruit Storage ◽

Cell Wall Assembly ◽

Wall Assembly

Arabinogalactan proteins (AGPs) are constituents of the cell wall–plasma membrane continuum in fruit tissue. The aim of the study was to characterise AGPs contained in fruit by determination of their chemical structure and morphological properties. The results were obtained from in and ex situ investigations and a comparative analysis of AGPs present in Malus × domestica fruit at different stages of ripening from green fruit through the mature stage to over-ripening during fruit storage. The HPLC and colorimetric methods were used for analyses of the composition of monosaccharides and proteins in AGPs extracted from fruit. We have found that AGPs from fruit mainly consists of carbohydrate chains composed predominantly of arabinose, galactose, glucose, galacturonic acid, and xylose. The protein moiety accounts for 3.15–4.58%, which depends on the various phases of ripening. Taken together, our results show that the structural and morphological properties of AGPs and calcium concentration in AGPs are related to the progress of ripening, which is correlated with proper fruit cell wall assembly. In line with the existing knowledge, our data confirmed the typical carbohydrate composition of AGPs and may be the basis for studies regarding their presumed properties of binding calcium ions.

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Cellulose synthase interactive1- and microtubule-dependent cell wall architecture is required for acid growth in Arabidopsis hypocotyls

Journal of Experimental Botany ◽

10.1093/jxb/eraa063 ◽

2020 ◽

Vol 71 (10) ◽

pp. 2982-2994 ◽

Cited By ~ 1

Author(s):

Xiaoran Xin ◽

Lei Lei ◽

Yunzhen Zheng ◽

Tian Zhang ◽

Sai Venkatesh Pingali ◽

...

Keyword(s):

Cell Wall ◽

Cell Elongation ◽

Plant Cell Wall ◽

Cellulose Microfibrils ◽

Crystalline Cellulose ◽

Cellulose Content ◽

Acid Growth ◽

Cell Wall Assembly ◽

Dependent Cell ◽

Cell Wall Architecture

Abstract Auxin-induced cell elongation relies in part on the acidification of the cell wall, a process known as acid growth that presumably triggers expansin-mediated wall loosening via altered interactions between cellulose microfibrils. Cellulose microfibrils are a major determinant for anisotropic growth and they provide the scaffold for cell wall assembly. Little is known about how acid growth depends on cell wall architecture. To explore the relationship between acid growth-mediated cell elongation and plant cell wall architecture, two mutants (jia1-1 and csi1-3) that are defective in cellulose biosynthesis and cellulose microfibril organization were analyzed. The study revealed that cell elongation is dependent on CSI1-mediated cell wall architecture but not on the overall crystalline cellulose content. We observed a correlation between loss of crossed-polylamellate walls and loss of auxin- and fusicoccin-induced cell growth in csi1-3. Furthermore, induced loss of crossed-polylamellate walls via disruption of cortical microtubules mimics the effect of csi1 in acid growth. We hypothesize that CSI1- and microtubule-dependent crossed-polylamellate walls are required for acid growth in Arabidopsis hypocotyls.

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